“A lot of guys have to go further offshore,’’ he said. “They’re being forced to go out in tough conditions, or they’ll lose their days. You’ve got to make a living.’’

In an effort to promote better safety on the water, DiMeo recently teamed up with the Coast Guard and hosted a Commercial Fishing Vessel Safety Day for local fishermen.

The event, held at the Marshfield airport, provided an opportunity for fishermen, charter boat operators, and other mariners to climb aboard a Coast Guard response boat and view an MH-60T Jayhawk helicopter up close. Coast Guard personnel demonstrated how to use flares, de-watering pumps, and survival suits, and talked about the life-saving techniques they use during rescue operations and responding to emergencies off the coast of Massachusetts, which can happen on a weekly basis.

Jonathan Wiggs/Globe Staff

Those attending had a chance to check out a Jayhawk helicopter used in rescues at sea.

Commercial fishing remains one of the most dangerous occupations in the country, with about 46 fishermen dying on the job every year, according to the National Institute for Occupational Safety and Health. The most recent death off local waters occurred last Nov. 28, east of Cape Cod. A Coast Guard MH-60 Jayhawk helicopter picked up a fisherman who had apparently suffered a heart attack.

Of the 545 commercial fishermen who died in the United States from 2000 through 2010, 279 of them, or more than half, were involved in a vessel disaster at sea; 170, or 31 percent, fell overboard; and about 10 percent sustained an injury on board.

John F. Buckley, the Coast Guard’s commercial fishing vessel safety coordinator for the region, said a hole the size of a quarter can flood a boat very quickly, and a small fire can engulf a vessel in minutes.

Because every second counts, mariners need to know where their safety equipment is and how to use it properly. Being prepared and knowing what to expect in an emergency is key.

Jessica L. Gill, a Coast Guard Boatswain’s Mate at Station Point Allerton in Hull, showed mariners the 25-foot response boat and explained how it is used for search-and-rescue operations as well as law enforcement. Several people asked what paperwork they needed to carry on their vessels, and how they can avoid getting stopped by authorities.

The Coast Guard flight crew happily answered questions about the helicopter, and explained how they use its rescue basket to evacuate people from boats in trouble.

“Everything operates more smoothly if everyone is on the same page,’’ said copilot Zephyr Mays.

Beth Casoni, associate executive director of the Massachusetts Lobstermen’s Association, said many lobstermen today can’t afford to hire extra help in this economy. “A lot of these guys fish alone,’’ which makes safety and emergency preparedness even more important, she said.

She was happy to see several members of her organization among the 100 or more people attending the safety event.

At the March 7 session, Coast Guard officials provided information on the latest federal safety requirements for fishermen and encouraged them to develop a preventive maintenance plan for their vessels and get them inspected. They also urged them to check their safety and survival equipment - such as fire extinguishers, survival suits, life rafts, emergency position-indicating radio beacons (known as EPIRBs), alarms, life-ring buoys, and first aid kits - to see if anything is missing, broken, or otherwise needs to be replaced.

“We have big concerns with safety,’’ said Steve James, a resident of Green Harbor and president of the Stellwagen Bank Charter Boat Association, who attended the event. “It’s all great to have safety equipment . . . but if you don’t familiarize yourself with it on a daily basis, it’s out of sight, out of mind.’’

James and his colleagues take people offshore-fishing on vessels between 30 and 50 feet long, known as “six-pack charters’’ because they are limited to carrying up to six paying passengers at a time. He said knowing the procedures for evacuating people is critical in an emergency, when “time is very much of the essence.’’

And if someone is having a heart attack on the boat, “there are things you could do to help out,’’ to make the rescue go smoothly, he said. It’s important to know what to expect and how to deal with things that you might not think about much, such as “rotor wash,’’ the forceful blast of air that comes down from spinning helicopter blades and stirs up the water.

Phil Mason, a 73-year-old fisherman from Marshfield, was happy to get a close-up look at the Coast Guard helicopter and rescue equipment. “I never got that close to a helicopter before,’’ he said. He listened as the flight crew explained how they drop a weighted line and evacuate passengers with the rescue basket. He said it was helpful hearing about what to expect, and what he should do, if the helicopter ever had to get to his boat. “You have to clear the decks,’’ he said. “You have to make sure everything is secure.’’

Mason said the session was informative and yielded important advice. With the economy the way it is, he said, working fishermen sometimes are tempted to cut corners, such as on equipment maintenance. He recalls that one fellow fisherman recently discovered he couldn’t fit into his survival suit anymore because he had put on a few extra pounds. That’s something you need to know before an emergency, not during one.

“Sometimes guys neglect that,’’ said Mason. “They fish on days they shouldn’t fish, because they need the income. Your break-even point becomes narrower and narrower,’’ he said.

Nathaniel “Laddie’’ Dexter, a 72-year-old Marshfield resident who has fished for more than 50 years, said attending the safety session was well worth the time.

“It could save a life,’’ he said. “It is a dangerous occupation.’’

Dexter catches lobsters and owns a 42-foot work boat called Happy Days. He doesn’t catch as much as he used to, and his son, Gregg, is now captain of the boat, which is docked at Green Harbor.

He said today’s technology and equipment make the job safer for fishermen than in the past. “We’re not as apt to get caught in ridiculous storms,’’ he said. “There’s new equipment all the time. From when I started to what we have now is absolutely incredible.’’

Dexter was happy to chat with the Coast Guard flight crew and check out the helicopter and response boat - two vehicles he said he doesn’t ever want to need at sea.

“I never want to see that door open over me with that basket ready to come down!’’ he said, looking at the Jayhawk.